The present disclosure relates generally to the cooling of high power density devices, and particularly to the use of turbomachinery for cooling high power density devices.
The cooling of high power density devices (HPDD's), such as high power density integrated circuits (IC's) and central processing units (CPU's) for example, is a significant consideration in the design of computer servers, military avionic equipment, medical imaging equipment, and other systems employing high power density electronic devices. The term HPDD used herein refers to heat generating devices having a heat flux in excess of 100 Watts-per-square-centimeter. Today's trend is not only to design electronic systems with greater and greater computational speed and power, but also to design them with smaller and smaller footprints, the end result being a HPDD that generates a lot of heat in a small area that needs to be dissipated in order to avoid IC and CPU degradation. While the power density of today's electronic systems may be as high as 200 watts per square centimeter (W/sq-cm), the trend is toward 800 W/sq-cm or beyond over the next several years. In addition to heat generation, enclosure size constraints must also be taken into consideration. For example, today's computer servers typically employ circuit boards that are housed in enclosures with a height restriction of 1.75 inches, referred to as a 1U application, with multiple circuit boards being stacked adjacent one another in a rack chassis. With a typical electronic component having an ambient use temperature of no greater than 120 degree-Celsius (deg-C.) and a junction temperature restriction of 90 deg-C., cooling systems are employed to transfer the heat of the HPDD to the surrounding ambient. Typical cooling systems employed today include fans, blowers, heat sinks, and refrigeration systems, which tend to increase in size as the heat transfer demands increase. This size increase, however, is contrary to the design objective of a 1U application.